Optical Mark Reading cardShort for Optical Mark Reading or Optical Mark Readers, OMR is a system that gathers information by using a hardware device that detects a reflection or an absence of reflection from a card or piece of paper. OMR enables the processing of hundreds or thousands of documents every hour automatically.

OMR processing is popular for tests, where students receive a special card containing several empty circles and a packet that contains the questions and possible answers to each of the questions. The student must complete the test by using a pencil to fill in each blank circle with what he or she believes is the correct answer. For example, if the answer is "B", the student would have to fill in the "B Circle" in order to get the answer correct.

Once the card or form has been completed a user would feed the cards into a system that grades or gathers information from the card. An example of an OMR system is the Scanmark 5500 from Scantron, a system that is capable of processing 5,500 documents every hour.

Also see: Input device, Punch card